UnitedHealth (UNH) 10-Q 6 Nov 19 2019 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information Document - shares	9 Months Ended
	Sep. 30, 2019	Oct. 31, 2019
Document and Entity Information [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2019
Document Transition Report	false
Entity File Number	1-10864
Entitiy Registrant Name	UnitedHealth Group Incorporated
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	41-1321939
Entity Address, Address Line One	UnitedHealth Group Center
Entity Address, Address Line Two	9900 Bren Road East
Entity Address, City or Town	Minnetonka,
Entity Address, State or Province	MN
Entity Address, Postal Zip Code	55343
City Area Code	952
Local Phone Number	936-1300
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Title of 12(b) Security	Common Stock, $.01 par value
Trading Symbol	UNH
Security Exchange Name	NYSE
Entitiy Central Index Key	0000731766
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q3
Amendment Flag	false
Entity Common Stock, Shares Outstanding		947,414,929

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 12,363	$ 10,866
Short-term investments	3,455	3,458
Accounts receivable, net	10,964	11,388
Other current receivables, net	10,152	6,862
Assets under management	3,051	3,032
Prepaid expenses and other current assets	3,556	3,086
Total current assets	43,541	38,692
Long-term investments	36,840	32,510
Property, equipment and capitalized software, net	8,501	8,458
Goodwill	65,205	58,910
Other intangible assets, net	10,521	9,325
Other assets	9,101	4,326
Total assets	173,709	152,221
Current liabilities:
Medical costs payable	20,939	19,891
Accounts payable and accrued liabilities	18,570	16,705
Commercial paper and current maturities of long-term debt	6,387	1,973
Unearned revenues	2,500	2,396
Other current liabilities	14,245	12,244
Total current liabilities	62,641	53,209
Long-term debt, less current maturities	38,507	34,581
Deferred income taxes	2,902	2,474
Other liabilities	9,912	5,730
Total liabilities	113,962	95,994
Commitments and contingencies (Note 7)
Redeemable noncontrolling interests	1,991	1,908
Equity:
Preferred stock, $0.001 par value - 10 shares authorized; no shares issued or outstanding	0	0
Common stock, $0.01 par value - 3,000 shares authorized; 947 and 960 issued and outstanding	9	10
Retained earnings	58,696	55,846
Accumulated other comprehensive loss	(3,709)	(4,160)
Nonredeemable noncontrolling interests	2,760	2,623
Total equity	57,756	54,319
Total liabilities, redeemable noncontrolling interests and equity	$ 173,709	$ 152,221

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheet (Parenthetical) - $ / shares shares in Millions	Sep. 30, 2019	Dec. 31, 2018
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	3,000	3,000
Common stock, shares issued	947	960
Common stock, shares outstanding	947	960
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	10	10
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations - USD ($) shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Revenues:
Premiums	$ 47,397	$ 44,613	$ 142,074	$ 133,155
Products	7,546	7,344	23,971	21,050
Services	4,942	4,217	13,756	12,590
Investment and other income	466	382	1,453	1,035
Total revenues	60,351	56,556	181,254	167,830
Operating costs:
Medical costs	39,041	36,158	117,164	108,448
Operating costs	8,960	8,479	25,892	25,371
Cost of products sold	6,627	6,718	21,606	19,373
Depreciation and amortization	709	611	2,002	1,791
Total operating costs	55,337	51,966	166,664	154,983
Earnings from operations	5,014	4,590	14,590	12,847
Interest expense	(449)	(353)	(1,267)	(1,026)
Earnings before income taxes	4,565	4,237	13,323	11,821
Provision for income taxes	(936)	(953)	(2,752)	(2,603)
Net earnings	3,629	3,284	10,571	9,218
Earnings attributable to noncontrolling interests	(91)	(96)	(273)	(272)
Net earnings attributable to UnitedHealth Group common shareholders	$ 3,538	$ 3,188	$ 10,298	$ 8,946
Earnings per share attributable to UnitedHealth Group common shareholders:
Basic	$ 3.73	$ 3.31	$ 10.82	$ 9.29
Diluted	$ 3.67	$ 3.24	$ 10.65	$ 9.09
Basic weighted-average number of common shares outstanding	949	962	952	963
Dilutive effect of common share equivalents	14	21	15	21
Diluted weighted-average number of common shares outstanding	963	983	967	984
Anti-dilutive shares excluded from the calculation of dilutive effect of common share equivalents	12	7	10	7

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Net earnings	$ 3,629	$ 3,284	$ 10,571	$ 9,218
Other comprehensive (loss) income:
Gross unrealized gains (losses) on investment securities during the period	230	(91)	1,243	(512)
Income tax effect	(53)	21	(285)	117
Total unrealized gains (losses), net of tax	177	(70)	958	(395)
Gross reclassification adjustment for net realized gains included in net earnings	(69)	(3)	(70)	(58)
Income tax effect	16	0	16	13
Total reclassification adjustment, net of tax	(53)	(3)	(54)	(45)
Total foreign currency translation losses	(560)	(233)	(453)	(1,303)
Other comprehensive (loss) income	(436)	(306)	451	(1,743)
Comprehensive income	3,193	2,978	11,022	7,475
Comprehensive income attributable to noncontrolling interests	(91)	(96)	(273)	(272)
Comprehensive income attributable to UnitedHealth Group common shareholders	$ 3,102	$ 2,882	$ 10,749	$ 7,203

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Changes in Equity - USD ($) shares in Millions, $ in Millions	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Retained Earnings [Member]	Net Unrealized (Losses) Gains on Investments [Member]	Foreign Currency Translation [Member]	Nonredeemable Noncontrolling Interests [Member]
Balance at Dec. 31, 2017	$ 49,833	$ 10	$ 1,703	$ 48,730	$ (13)	$ (2,654)	$ 2,057
Balance (in shares) at Dec. 31, 2017		969
Adjustment to adopt ASU at Dec. 31, 2017	0			(24)	24
Net earnings attributable to UnitedHealth Group common shareholders	8,946			8,946
Net earnings attributable to nonredeemable noncontrolling interest							183
Net Earnings, Including Portion Attributable to Nonredeemable Noncontrolling Interest	9,129
Other comprehensive income (loss)	(1,743)				(440)	(1,303)
Issuances of common stock, and related tax effects (in shares)		9
Issuances of common stock, and related tax effects	761	$ 0	761
Share-based compensation	493		493
Common share repurchases (in shares)		(16)
Common share repurchases	(3,650)	$ 0	(2,838)	(812)
Cash dividends paid on common shares	(2,454)			(2,454)
Redeemable noncontrolling interests fair value and other adjustments	(119)		(119)
Acquisition and other adjustments of nonredeemable noncontrolling interests	518						518
Distribution to nonredeemable noncontrolling interests	(172)						(172)
Balance at Sep. 30, 2018	52,596	$ 10	0	54,386	(429)	(3,957)	2,586
Balance (in shares) at Sep. 30, 2018		962
Balance at Jun. 30, 2018	50,783	$ 10	0	52,363	(356)	(3,724)	2,490
Balance (in shares) at Jun. 30, 2018		962
Net earnings attributable to UnitedHealth Group common shareholders	3,188			3,188
Net earnings attributable to nonredeemable noncontrolling interest							71
Net Earnings, Including Portion Attributable to Nonredeemable Noncontrolling Interest	3,259
Other comprehensive income (loss)	(306)				(73)	(233)
Issuances of common stock, and related tax effects (in shares)		2
Issuances of common stock, and related tax effects	239	$ 0	239
Share-based compensation	146		146
Common share repurchases (in shares)		(2)
Common share repurchases	(500)	$ 0	(201)	(299)
Cash dividends paid on common shares	(866)			(866)
Redeemable noncontrolling interests fair value and other adjustments	(184)		(184)
Acquisition and other adjustments of nonredeemable noncontrolling interests	102						102
Distribution to nonredeemable noncontrolling interests	(77)						(77)
Balance at Sep. 30, 2018	52,596	$ 10	0	54,386	(429)	(3,957)	2,586
Balance (in shares) at Sep. 30, 2018		962
Balance at Dec. 31, 2018	$ 54,319	$ 10	0	55,846	(264)	(3,896)	2,623
Balance (in shares) at Dec. 31, 2018	960	960
Adjustment to adopt ASU at Dec. 31, 2018	$ (18)			(13)			(5)
Net earnings attributable to UnitedHealth Group common shareholders	10,298			10,298
Net earnings attributable to nonredeemable noncontrolling interest							196
Net Earnings, Including Portion Attributable to Nonredeemable Noncontrolling Interest	10,494
Other comprehensive income (loss)	451				904	(453)
Issuances of common stock, and related tax effects (in shares)		8
Issuances of common stock, and related tax effects	438	$ 0	438
Share-based compensation	521		521
Common share repurchases (in shares)		(21)
Common share repurchases	(5,101)	$ (1)	(573)	(4,527)
Cash dividends paid on common shares	(2,908)			(2,908)
Redeemable noncontrolling interests fair value and other adjustments	(277)		(277)
Acquisition and other adjustments of nonredeemable noncontrolling interests	48		(109)				157
Distribution to nonredeemable noncontrolling interests	(211)						(211)
Balance at Sep. 30, 2019	$ 57,756	$ 9	0	58,696	640	(4,349)	2,760
Balance (in shares) at Sep. 30, 2019	947	947
Balance at Jun. 30, 2019	$ 55,854	$ 9	0	56,367	516	(3,789)	2,751
Balance (in shares) at Jun. 30, 2019		948
Net earnings attributable to UnitedHealth Group common shareholders	3,538			3,538
Net earnings attributable to nonredeemable noncontrolling interest							82
Net Earnings, Including Portion Attributable to Nonredeemable Noncontrolling Interest	3,620
Other comprehensive income (loss)	(436)				124	(560)
Issuances of common stock, and related tax effects (in shares)		2
Issuances of common stock, and related tax effects	277	$ 0	277
Share-based compensation	130		130
Common share repurchases (in shares)		(3)
Common share repurchases	(600)	$ 0	(415)	(185)
Cash dividends paid on common shares	(1,024)			(1,024)
Redeemable noncontrolling interests fair value and other adjustments	8		8
Acquisition and other adjustments of nonredeemable noncontrolling interests	(7)						(7)
Distribution to nonredeemable noncontrolling interests	(66)						(66)
Balance at Sep. 30, 2019	$ 57,756	$ 9	$ 0	$ 58,696	$ 640	$ (4,349)	$ 2,760
Balance (in shares) at Sep. 30, 2019	947	947

Condensed Consolidated Statem_4

Condensed Consolidated Statement of Changes in Equity (Parenthetical) - USD ($) $ in Millions	Sep. 24, 2019	Jun. 25, 2019	Mar. 19, 2019	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement of Stockholders' Equity [Abstract]
Common Stock, Dividends, Per Share, Cash Paid	$ 1.08	$ 1.08	$ 0.90	$ 1.08	$ 0.90	$ 3.06	$ 2.55
Payments of Ordinary Dividends, Common Stock	$ 1,024	$ 1,024	$ 860			$ 2,908	$ 2,454

Condensed Consolidated Statem_5

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Operating activities
Net earnings	$ 10,571	$ 9,218
Noncash items:
Depreciation and amortization	2,002	1,791
Deferred income taxes	177	9
Share-based compensation	525	512
Other, net	(181)	(136)
Net change in other operating items, net of effects from acquisitions and changes in AARP balances:
Accounts receivable	957	(984)
Other assets	(2,181)	(1,641)
Medical costs payable	223	1,745
Accounts payable and other liabilities	105	2,783
Unearned revenues	60	20
Cash flows from operating activities	12,258	13,317
Investing activities
Purchases of investments	(13,386)	(11,316)
Sales of investments	6,198	2,872
Maturities of investments	5,160	4,715
Cash paid for acquisitions, net of cash assumed	(8,200)	(5,824)
Purchases of property, equipment and capitalized software	(1,421)	(1,505)
Other, net	338	(187)
Cash flows used for investing activities	(11,311)	(11,245)
Financing activities
Common share repurchases	(5,101)	(3,650)
Cash dividends paid	(2,908)	(2,454)
Proceeds from common stock issuances	740	745
Repayments of long-term debt	(1,250)	(2,600)
Proceeds from (repayments of) commercial paper, net	3,998	(164)
Proceeds from issuance of long-term debt	5,444	3,964
Customer funds administered	420	1,552
Other, net	(756)	(1,086)
Cash flows from (used for) financing activities	587	(3,693)
Effect of exchange rate changes on cash and cash equivalents	(37)	(97)
Increase (decrease) in cash and cash equivalents	1,497	(1,718)
Cash and cash equivalents, beginning of period	10,866	11,981
Cash and cash equivalents, end of period	$ 12,363	$ 10,263

Basis of Presentation (Notes)

Basis of Presentation (Notes)	9 Months Ended
	Sep. 30, 2019
Basis of Presentation and Significant Accounting Policies [Text Block]	Basis of Presentation UnitedHealth Group Incorporated (individually and together with its subsidiaries, “UnitedHealth Group” and the “Company”) is a diversified health care company dedicated to helping people live healthier lives and helping make the health system work better for everyone. Through its diversified family of businesses, the Company leverages core competencies in data and health information; advanced technology; and clinical expertise. These core competencies are deployed within two distinct, but strategically aligned, business platforms: health benefits operating under UnitedHealthcare and health services operating under Optum. The Company has prepared the Condensed Consolidated Financial Statements according to U.S. Generally Accepted Accounting Principles (GAAP) and has included the accounts of UnitedHealth Group and its subsidiaries. The year-end condensed consolidated balance sheet was derived from audited financial statements, but does not include all disclosures required by GAAP. In accordance with the rules and regulations of the U.S. Securities and Exchange Commission (SEC), the Company has omitted certain footnote disclosures that would substantially duplicate the disclosures contained in its annual audited Consolidated Financial Statements. Therefore, these Condensed Consolidated Financial Statements should be read together with the Consolidated Financial Statements and the Notes included in Part II, Item 8, “Financial Statements and Supplementary Data” in the Company’s Annual Report on Form 10-K for the year ended December 31, 2018 as filed with the SEC ( 2018 10-K). The accompanying Condensed Consolidated Financial Statements include all normal recurring adjustments necessary to present the interim financial statements fairly. Use of Estimates These Condensed Consolidated Financial Statements include certain amounts based on the Company’s best estimates and judgments. The Company’s most significant estimates include medical costs payable and goodwill. Certain of these estimates require the application of complex assumptions and judgments, often because they involve matters that are inherently uncertain and will likely change in subsequent periods. The impact of any change in estimates is included in earnings in the period in which the estimate is adjusted. Recently Adopted Accounting Standards In February 2016, the Financial Accounting Standards Board (FASB) issued Accounting Standard Update (ASU) No. 2016-02, “Leases (Topic 842)” as modified by ASUs 2018-01, 2018-10, 2018-11, 2018-20 and 2019-01 (collectively, ASU 2016-02). Under ASU 2016-02, an entity is required to recognize assets and liabilities for the rights and obligations created by leases on the entity’s balance sheet for both finance and operating leases. The Company adopted ASU 2016-02 using a cumulative-effect upon adoption approach as of January 1, 2019. Upon adoption, the Company recognized $3.3 billion of lease right-of-use (ROU) assets and liabilities for operating leases on its Condensed Consolidated Balance Sheet, of which, $668 million were classified as current liabilities. The adoption of ASU 2016-02 was immaterial to the Company’s consolidated results of operations, equity and cash flows. The Company has included the disclosures required by ASU 2016-02 below and in Note 7, “Commitments and Contingencies.” The Company leases facilities and equipment under long-term operating leases that are non-cancelable and expire on various dates. At the lease commencement date, lease ROU assets and lease liabilities are recognized based on the present value of the future minimum lease payments over the lease term, which includes all fixed obligations arising from the lease contract. If an interest rate is not implicit in a lease, the Company utilizes its incremental borrowing rate for a period that closely matches the lease term. The Company’s ROU assets are included in other assets, and lease liabilities are included in other current liabilities and other liabilities in the Company’s Condensed Consolidated Balance Sheet. The Company has determined that there have been no other recently adopted or issued accounting standards that had, or will have, a material impact on its Condensed Consolidated Financial Statements.

Investments (Notes)

Investments (Notes)	9 Months Ended
	Sep. 30, 2019
Investments [Abstract]
Investments [Text Block]	Investments A summary of debt securities by major security type is as follows: (in millions) Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value September 30, 2019 Debt securities - available-for-sale: U.S. government and agency obligations $ 3,591 $ 83 $ (2 ) $ 3,672 State and municipal obligations 5,657 256 (3 ) 5,910 Corporate obligations 17,824 352 (9 ) 18,167 U.S. agency mortgage-backed securities 6,361 113 (6 ) 6,468 Non-U.S. agency mortgage-backed securities 1,685 48 (1 ) 1,732 Total debt securities - available-for-sale 35,118 852 (21 ) 35,949 Debt securities - held-to-maturity: U.S. government and agency obligations 272 2 — 274 State and municipal obligations 32 1 — 33 Corporate obligations 547 — — 547 Total debt securities - held-to-maturity 851 3 — 854 Total debt securities $ 35,969 $ 855 $ (21 ) $ 36,803 December 31, 2018 Debt securities - available-for-sale: U.S. government and agency obligations $ 3,434 $ 13 $ (42 ) $ 3,405 State and municipal obligations 7,117 61 (57 ) 7,121 Corporate obligations 15,366 14 (218 ) 15,162 U.S. agency mortgage-backed securities 4,947 11 (106 ) 4,852 Non-U.S. agency mortgage-backed securities 1,376 2 (20 ) 1,358 Total debt securities - available-for-sale 32,240 101 (443 ) 31,898 Debt securities - held-to-maturity: U.S. government and agency obligations 255 1 (2 ) 254 State and municipal obligations 11 — — 11 Corporate obligations 355 — — 355 Total debt securities - held-to-maturity 621 1 (2 ) 620 Total debt securities $ 32,861 $ 102 $ (445 ) $ 32,518 The Company held $2.0 billion of equity securities as of both September 30, 2019 and December 31, 2018 . The Company’s investments in equity securities primarily consist of employee savings plan related investments, shares of Brazilian real denominated fixed-income funds and dividend paying stocks with readily determinable fair values. Additionally, the Company’s investments included $1.4 billion and $1.5 billion of equity method investments in operating businesses in the health care sector as of September 30, 2019 and December 31, 2018 , respectively. The amortized cost and fair value of debt securities as of September 30, 2019 , by contractual maturity, were as follows: Available-for-Sale Held-to-Maturity (in millions) Amortized Cost Fair Value Amortized Fair Due in one year or less $ 3,571 $ 3,577 $ 313 $ 313 Due after one year through five years 11,904 12,084 258 259 Due after five years through ten years 8,303 8,669 141 141 Due after ten years 3,294 3,419 139 141 U.S. agency mortgage-backed securities 6,361 6,468 — — Non-U.S. agency mortgage-backed securities 1,685 1,732 — — Total debt securities $ 35,118 $ 35,949 $ 851 $ 854 The fair value of available-for-sale debt securities with gross unrealized losses by security type and length of time that individual securities have been in a continuous unrealized loss position were as follows: Less Than 12 Months 12 Months or Greater Total (in millions) Fair Value Gross Unrealized Losses Fair Value Gross Fair Value Gross September 30, 2019 Debt securities - available-for-sale: U.S. government and agency obligations $ 286 $ (1 ) $ 228 $ (1 ) $ 514 $ (2 ) State and municipal obligations 296 (2 ) 83 (1 ) 379 (3 ) Corporate obligations 1,360 (5 ) 1,022 (4 ) 2,382 (9 ) U.S. agency mortgage-backed securities 570 (2 ) 518 (4 ) 1,088 (6 ) Non-U.S. agency mortgage-backed securities 217 (1 ) — — 217 (1 ) Total debt securities - available-for-sale $ 2,729 $ (11 ) $ 1,851 $ (10 ) $ 4,580 $ (21 ) December 31, 2018 Debt securities - available-for-sale: U.S. government and agency obligations $ 998 $ (7 ) $ 1,425 $ (35 ) $ 2,423 $ (42 ) State and municipal obligations 1,334 (11 ) 2,491 (46 ) 3,825 (57 ) Corporate obligations 8,105 (109 ) 4,239 (109 ) 12,344 (218 ) U.S. agency mortgage-backed securities 1,296 (22 ) 2,388 (84 ) 3,684 (106 ) Non-U.S. agency mortgage-backed securities 622 (7 ) 459 (13 ) 1,081 (20 ) Total debt securities - available-for-sale $ 12,355 $ (156 ) $ 11,002 $ (287 ) $ 23,357 $ (443 ) The Company’s unrealized losses from debt securities as of September 30, 2019 were generated from 4,000 positions out of a total of 32,000 positions. The Company believes that it will collect the principal and interest due on its debt securities that have an amortized cost in excess of fair value. The unrealized losses were primarily caused by interest rate increases and not by unfavorable changes in the credit quality associated with these securities. At each reporting period, the Company evaluates securities for impairment when the fair value of the investment is less than its amortized cost. The Company evaluated the underlying credit quality and credit ratings of the issuers, noting no significant deterioration since purchase. As of September 30, 2019 , the Company did not have the intent to sell any of the securities in an unrealized loss position. Therefore, the Company believes these losses to be temporary.

Fair Value (Notes)

Fair Value (Notes)	9 Months Ended
	Sep. 30, 2019
Fair Value Disclosures [Abstract]
Fair Value [Text Block]	Fair Value Certain assets and liabilities are measured at fair value in the Condensed Consolidated Financial Statements or have fair values disclosed in the Notes to the Condensed Consolidated Financial Statements. These assets and liabilities are classified into one of three levels of a hierarchy defined by GAAP. For a description of the methods and assumptions that are used to estimate the fair value and determine the fair value hierarchy classification of each class of financial instrument, see Note 4 of Notes to the Consolidated Financial Statements in Part II, Item 8, “Financial Statements and Supplementary Data” in the 2018 10-K. The following table presents a summary of fair value measurements by level and carrying values for items measured at fair value on a recurring basis in the Condensed Consolidated Balance Sheets: (in millions) Quoted Prices in Active Markets (Level 1) Other Observable Inputs (Level 2) Unobservable Inputs (Level 3) Total Fair and Carrying Value September 30, 2019 Cash and cash equivalents $ 12,210 $ 153 $ — $ 12,363 Debt securities - available-for-sale: U.S. government and agency obligations 3,421 251 — 3,672 State and municipal obligations — 5,910 — 5,910 Corporate obligations 71 17,879 217 18,167 U.S. agency mortgage-backed securities — 6,468 — 6,468 Non-U.S. agency mortgage-backed securities — 1,732 — 1,732 Total debt securities - available-for-sale 3,492 32,240 217 35,949 Equity securities 1,839 21 — 1,860 Assets under management 1,116 1,907 28 3,051 Total assets at fair value $ 18,657 $ 34,321 $ 245 $ 53,223 Percentage of total assets at fair value 35 % 65 % — % 100 % December 31, 2018 Cash and cash equivalents $ 10,757 $ 109 $ — $ 10,866 Debt securities - available-for-sale: U.S. government and agency obligations 3,060 345 — 3,405 State and municipal obligations — 7,121 — 7,121 Corporate obligations 39 14,950 173 15,162 U.S. agency mortgage-backed securities — 4,852 — 4,852 Non-U.S. agency mortgage-backed securities — 1,358 — 1,358 Total debt securities - available-for-sale 3,099 28,626 173 31,898 Equity securities 1,832 13 — 1,845 Assets under management 1,086 1,938 8 3,032 Total assets at fair value $ 16,774 $ 30,686 $ 181 $ 47,641 Percentage of total assets at fair value 35 % 65 % — % 100 % There were no transfers in or out of Level 3 financial assets or liabilities during the nine months ended September 30, 2019 or 2018 . The following table presents a summary of fair value measurements by level and carrying values for certain financial instruments not measured at fair value on a recurring basis in the Condensed Consolidated Balance Sheets: (in millions) Quoted Prices in Active Markets (Level 1) Other Observable Inputs (Level 2) Unobservable Inputs (Level 3) Total Fair Value Total Carrying Value September 30, 2019 Debt securities - held-to-maturity $ 410 $ 176 $ 268 $ 854 $ 851 Long-term debt and other financing obligations $ — $ 45,342 $ — $ 45,342 $ 40,814 December 31, 2018 Debt securities - held-to-maturity $ 260 $ 65 $ 295 $ 620 $ 621 Long-term debt and other financing obligations $ — $ 37,944 $ — $ 37,944 $ 36,554 Nonfinancial assets and liabilities or financial assets and liabilities that are measured at fair value on a nonrecurring basis are subject to fair value adjustments only in certain circumstances, such as when the Company records an impairment. There were no significant fair value adjustments for these assets and liabilities recorded during either the nine months ended September 30, 2019 or 2018 .

Medical Costs Payable (Notes)

Medical Costs Payable (Notes)	9 Months Ended
	Sep. 30, 2019
Medical Costs Payable Text Block	Medical Costs Payable The following table shows the components of the change in medical costs payable for the nine months ended September 30: (in millions) 2019 2018 Medical costs payable, beginning of period $ 19,891 $ 17,871 Acquisitions 868 333 Reported medical costs: Current year 117,624 108,658 Prior years (460 ) (210 ) Total reported medical costs 117,164 108,448 Medical payments: Payments for current year (99,487 ) (90,348 ) Payments for prior years (17,497 ) (16,454 ) Total medical payments (116,984 ) (106,802 ) Medical costs payable, end of period $ 20,939 $ 19,850 For the nine months ended September 30, 2019 and 2018 , the medical cost reserve development included no individual factors that were significant. Medical costs payable included reserves for claims incurred by insured customers but not yet reported to the Company of $14.2 billion and $13.2 billion at September 30, 2019 and December 31, 2018

Commercial Paper and Long-Term

Commercial Paper and Long-Term Debt (Notes)	9 Months Ended
	Sep. 30, 2019
Debt Disclosure [Abstract]
Commercial Paper and Long-Term Debt [Text Block]	Commercial Paper and Long-Term Debt Commercial paper and senior unsecured long-term debt consisted of the following: September 30, 2019 December 31, 2018 (in millions, except percentages) Par Value Carrying Value Fair Value Par Value Carrying Value Fair Value Commercial paper $ 4,082 $ 4,080 $ 4,080 $ — $ — $ — 1.700% notes due February 2019 — — — 750 750 749 1.625% notes due March 2019 — — — 500 500 499 2.300% notes due December 2019 500 499 500 500 494 497 2.700% notes due July 2020 1,500 1,499 1,508 1,500 1,498 1,494 Floating rate notes due October 2020 300 300 300 300 299 298 3.875% notes due October 2020 450 450 457 450 443 456 1.950% notes due October 2020 900 898 900 900 897 884 4.700% notes due February 2021 400 404 412 400 398 412 2.125% notes due March 2021 750 748 752 750 747 734 Floating rate notes due June 2021 350 349 349 350 349 347 3.150% notes due June 2021 400 399 408 400 399 400 3.375% notes due November 2021 500 502 512 500 489 503 2.875% notes due December 2021 750 755 764 750 735 748 2.875% notes due March 2022 1,100 1,088 1,120 1,100 1,051 1,091 3.350% notes due July 2022 1,000 997 1,036 1,000 997 1,005 2.375% notes due October 2022 900 895 909 900 894 872 0.000% notes due November 2022 15 13 13 15 12 13 2.750% notes due February 2023 625 627 637 625 602 611 2.875% notes due March 2023 750 776 769 750 750 739 3.500% notes due June 2023 750 747 786 750 746 756 3.500% notes due February 2024 750 745 790 750 745 755 2.375% notes due August 2024 750 746 756 — — — 3.750% notes due July 2025 2,000 1,990 2,150 2,000 1,989 2,025 3.700% notes due December 2025 300 298 323 300 298 303 3.100% notes due March 2026 1,000 996 1,045 1,000 995 965 3.450% notes due January 2027 750 746 798 750 746 742 3.375% notes due April 2027 625 619 663 625 619 611 2.950% notes due October 2027 950 939 982 950 938 898 3.850% notes due June 2028 1,150 1,142 1,259 1,150 1,142 1,163 3.875% notes due December 2028 850 843 936 850 842 861 2.875% notes due August 2029 1,000 1,022 1,021 — — — 4.625% notes due July 2035 1,000 992 1,208 1,000 992 1,060 5.800% notes due March 2036 850 838 1,134 850 838 1,003 6.500% notes due June 2037 500 492 711 500 492 638 6.625% notes due November 2037 650 641 940 650 641 841 6.875% notes due February 2038 1,100 1,076 1,625 1,100 1,076 1,437 3.500% notes due August 2039 1,250 1,241 1,301 — — — 5.700% notes due October 2040 300 296 397 300 296 355 5.950% notes due February 2041 350 345 476 350 345 426 4.625% notes due November 2041 600 589 710 600 588 627 4.375% notes due March 2042 502 484 572 502 484 503 3.950% notes due October 2042 625 607 676 625 607 596 4.250% notes due March 2043 750 735 844 750 734 744 4.750% notes due July 2045 2,000 1,973 2,431 2,000 1,973 2,116 4.200% notes due January 2047 750 738 852 750 738 745 4.250% notes due April 2047 725 717 823 725 717 719 3.750% notes due October 2047 950 933 1,005 950 933 869 4.250% notes due June 2048 1,350 1,329 1,550 1,350 1,329 1,349 4.450% notes due December 2048 1,100 1,086 1,301 1,100 1,087 1,132 3.700% notes due August 2049 1,250 1,235 1,323 — — — 3.875% notes due August 2059 1,250 1,231 1,327 — — — Total commercial paper and long-term debt $ 43,999 $ 43,690 $ 48,141 $ 35,667 $ 35,234 $ 36,591 The Company’s long-term debt obligations included $1.2 billion and $1.3 billion of other financing obligations, of which $309 million and $229 million were classified as current as of September 30, 2019 and December 31, 2018 , respectively. Commercial Paper and Bank Credit Facilities Commercial paper consists of short-duration, senior unsecured debt privately placed on a discount basis through broker-dealers. As of September 30, 2019 , the Company’s outstanding commercial paper had a weighted average annual interest rate of 2.2% . The Company has $3.5 billion five-year, $3.5 billion three-year and $3.0 billion 364-day revolving bank credit facilities with 26 banks, which mature in December 2023 , December 2021 and December 2019 , respectively. The Company additionally has a $2.5 billion 364-day revolving bank credit facility with 6 banks that matures in May 2020 . These facilities provide liquidity support for the Company’s commercial paper program and are available for general corporate purposes. As of September 30, 2019 , no amounts had been drawn on any of the bank credit facilities. The annual interest rates, which are variable based on term, are calculated based on the London Interbank Offered Rate (LIBOR) plus a credit spread based on the Company’s senior unsecured credit ratings. If amounts had been drawn on the bank credit facilities as of September 30, 2019 , annual interest rates would have ranged from 2.7% to 2.8% . Debt Covenants The Company’s bank credit facilities contain various covenants, including covenants requiring the Company to maintain a defined debt to debt-plus-shareholders’ equity ratio of not more than 60% . The Company was in compliance with its debt covenants as of September 30, 2019 .

Dividends (Notes)

Dividends (Notes)	9 Months Ended
	Sep. 30, 2019
Shareholders' Equity [Abstract]
Stockholders' Equity Note Disclosure [Text Block]	. Dividends In June 2019, the Company’s Board of Directors increased the Company’s annual dividend rate to shareholders to $4.32 compared to $3.60 per share, which the Company had paid since June 2018. Declaration and payment of future quarterly dividends is at the discretion of the Board and may be adjusted as business needs or market conditions change. The following table provides details of the Company’s 2019 dividend payments: Payment Date Amount per Share Total Amount Paid (in millions) March 19 $ 0.90 $ 860 June 25 1.08 1,024 September 24 1.08 1,024

Commitments and Contingencies (

Commitments and Contingencies (Notes)	9 Months Ended
	Sep. 30, 2019
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies Disclosure [Text Block]	Commitments and Contingencies Leases Operating lease costs were $275 million and $760 million for the three and nine months ended September 30, 2019 , respectively, and included immaterial variable and short-term lease costs. Cash payments made on the Company’s operating lease liabilities were $552 million for the nine months ended September 30, 2019 , which were classified within operating activities in the Condensed Consolidated Statements of Cash Flows. As of September 30, 2019 , the Company’s weighted-average remaining lease term and weighted-average discount rate for its operating leases were 8.6 years and 3.9% , respectively. As of September 30, 2019 , future minimum annual lease payments under all non-cancelable operating leases were as follows: (in millions) Future Operating Lease Payments 2019 $ 198 2020 782 2021 693 2022 580 2023 477 Thereafter 1,978 Total future minimum lease payments 4,708 Less imputed interest (758 ) Total $ 3,950 Legal Matters Because of the nature of its businesses, the Company is frequently made party to a variety of legal actions and regulatory inquiries, including class actions and suits brought by members, care providers, consumer advocacy organizations, customers and regulators, relating to the Company’s businesses, including management and administration of health benefit plans and other services. These matters include medical malpractice, employment, intellectual property, antitrust, privacy and contract claims and claims related to health care benefits coverage and other business practices. The Company records liabilities for its estimates of probable costs resulting from these matters where appropriate. Estimates of costs resulting from legal and regulatory matters involving the Company are inherently difficult to predict, particularly where the matters: involve indeterminate claims for monetary damages or may involve fines, penalties or punitive damages; present novel legal theories or represent a shift in regulatory policy; involve a large number of claimants or regulatory bodies; are in the early stages of the proceedings; or could result in a change in business practices. Accordingly, the Company is often unable to estimate the losses or ranges of losses for those matters where there is a reasonable possibility or it is probable that a loss may be incurred. Government Investigations, Audits and Reviews The Company has been involved or is currently involved in various governmental investigations, audits and reviews. These include routine, regular and special investigations, audits and reviews by the Centers for Medicare and Medicaid Services (CMS), state insurance and health and welfare departments, the Brazilian national regulatory agency for private health insurance and plans (the Agência Nacional de Saúde Suplementar), state attorneys general, the Office of the Inspector General, the Office of Personnel Management, the Office of Civil Rights, the Government Accountability Office, the Federal Trade Commission, U.S. Congressional committees, the U.S. Department of Justice, the SEC, the Internal Revenue Service, the U.S. Drug Enforcement Administration, the Brazilian federal revenue service (the Secretaria da Receita Federal), the U.S. Department of Labor, the Federal Deposit Insurance Corporation, the Defense Contract Audit Agency and other governmental authorities. Certain of the Company’s businesses have been reviewed or are currently under review, including for, among other matters, compliance with coding and other requirements under the Medicare risk-adjustment model. CMS has selected certain of the Company’s local plans for risk adjustment data validation (RADV) audits to validate the coding practices of and supporting documentation maintained by health care providers and such audits may result in retrospective adjustments to payments made to the Company’s health plans. On February 14, 2017, the Department of Justice (DOJ) announced its decision to pursue certain claims within a lawsuit initially asserted against the Company and filed under seal by a whistleblower in 2011. The whistleblower’s complaint, which was unsealed on February 15, 2017, alleges that the Company made improper risk adjustment submissions and violated the False Claims Act. On February 12, 2018, the court granted in part and denied in part the Company’s motion to dismiss. In May 2018, DOJ moved to dismiss the Company’s counterclaims, which were filed in March 2018, and moved for partial summary judgment. In March 2019, the court denied the government’s motion for partial summary judgment and dismissed the Company’s counterclaims without prejudice. The Company cannot reasonably estimate the outcome that may result from this matter given its procedural status.

Business Combinations (Notes)

Business Combinations (Notes)	9 Months Ended
	Sep. 30, 2019
Business Combinations [Abstract]
Business Combination Disclosure [Text Block]	8. Business Combinations During the nine months ended September 30, 2019 , the Company completed several business combinations for total cash consideration of $9.7 billion . The total consideration exceeded the estimated fair value of the net tangible assets acquired by $8.6 billion , of which $2.0 billion has been allocated to finite-lived intangible assets and $6.6 billion to goodwill. The goodwill is not deductible for income tax purposes. Acquired tangible assets (liabilities) at acquisition date were: (in millions) Cash and cash equivalents $ 1,537 Accounts receivable and other current assets 1,775 Property, equipment and other long-term assets 1,941 Medical costs payable (868 ) Accounts payable and other current liabilities (1,669 ) Other long-term liabilities (1,283 ) Total net tangible assets $ 1,433 The preliminary purchase price allocations for the various business combinations are subject to adjustment as valuation analyses, primarily related to intangible assets and contingent and tax liabilities, are finalized. The acquisition date fair values and weighted-average useful lives assigned to acquired finite-lived intangible assets were: (in millions, except years) Fair Value Weighted-Average Useful Life Customer-related $ 1,670 14 Trademarks and technology 117 4 Other 164 10 Total acquired finite-lived intangible assets $ 1,951 13 The results of operations and financial condition of acquired entities have been included in the Company’s consolidated results and the results of the corresponding operating segment as of date of acquisition. Through September 30, 2019 , acquired entities’ impact on revenues and net earnings was not material. Unaudited pro forma revenues for the nine months ended September 30, 2019 and 2018 as if the acquisitions had occurred on January 1, 2018 were immaterial for both periods. The pro forma effects of the acquisitions on net earnings were immaterial for both years.

Segment Financial Information (

Segment Financial Information (Notes)	9 Months Ended
	Sep. 30, 2019
Segment Reporting [Abstract]
Segment Financial Information [Text Block]	Segment Financial Information The Company’s four reportable segments are UnitedHealthcare, OptumHealth, OptumInsight and OptumRx . For more information on the Company’s segments see Part I, Item I, “Business” and Note 13 of Notes to the Consolidated Financial Statements in Part II, Item 8, “Financial Statements and Supplementary Data” in the 2018 10-K. Total assets at OptumHealth increased to $40.1 billion as of September 30, 2019 compared to $29.8 billion as of December 31, 2018 , primarily due to goodwill and other intangibles assets from a second quarter 2019 acquisition and the recognition of ROU assets from ASU 2016-02. Total assets at OptumInsight increased to $15.1 billion as of September 30, 2019 compared to $11.0 billion as of December 31, 2018 , primarily due to goodwill and other intangibles assets from a third quarter 2019 acquisition. The following tables present reportable segment financial information: Optum (in millions) UnitedHealthcare OptumHealth OptumInsight OptumRx Optum Eliminations Optum Corporate and Eliminations Consolidated Three Months Ended September 30, 2019 Revenues - unaffiliated customers: Premiums $ 45,557 $ 1,840 $ — $ — $ — $ 1,840 $ — $ 47,397 Products — 6 29 7,511 — 7,546 — 7,546 Services 2,274 1,487 988 193 — 2,668 — 4,942 Total revenues - unaffiliated customers 47,831 3,333 1,017 7,704 — 12,054 — 59,885 Total revenues - affiliated customers — 4,630 1,594 10,734 (441 ) 16,517 (16,517 ) — Investment and other income 274 170 6 16 — 192 — 466 Total revenues $ 48,105 $ 8,133 $ 2,617 $ 18,454 $ (441 ) $ 28,763 $ (16,517 ) $ 60,351 Earnings from operations $ 2,655 $ 748 $ 632 $ 979 $ — $ 2,359 $ — $ 5,014 Interest expense — — — — — — (449 ) (449 ) Earnings before income taxes $ 2,655 $ 748 $ 632 $ 979 $ — $ 2,359 $ (449 ) $ 4,565 Three Months Ended September 30, 2018 Revenues - unaffiliated customers: Premiums $ 43,628 $ 985 $ — $ — $ — $ 985 $ — $ 44,613 Products — 13 29 7,302 — 7,344 — 7,344 Services 2,067 1,196 790 164 — 2,150 — 4,217 Total revenues - unaffiliated customers 45,695 2,194 819 7,466 — 10,479 — 56,174 Total revenues - affiliated customers — 3,733 1,431 9,960 (352 ) 14,772 (14,772 ) — Investment and other income 242 125 4 11 — 140 — 382 Total revenues $ 45,937 $ 6,052 $ 2,254 $ 17,437 $ (352 ) $ 25,391 $ (14,772 ) $ 56,556 Earnings from operations $ 2,559 $ 622 $ 534 $ 875 $ — $ 2,031 $ — $ 4,590 Interest expense — — — — — — (353 ) (353 ) Earnings before income taxes $ 2,559 $ 622 $ 534 $ 875 $ — $ 2,031 $ (353 ) $ 4,237 Optum (in millions) UnitedHealthcare OptumHealth OptumInsight OptumRx Optum Eliminations Optum Corporate and Consolidated Nine Months Ended September 30, 2019 Revenues - unaffiliated customers: Premiums $ 138,088 $ 3,986 $ — $ — $ — $ 3,986 $ — $ 142,074 Products — 23 74 23,874 — 23,971 — 23,971 Services 6,603 4,131 2,532 490 — 7,153 — 13,756 Total revenues - unaffiliated customers 144,691 8,140 2,606 24,364 — 35,110 — 179,801 Total revenues - affiliated customers — 13,366 4,522 30,786 (1,181 ) 47,493 (47,493 ) — Investment and other income 904 488 17 44 — 549 — 1,453 Total revenues $ 145,595 $ 21,994 $ 7,145 $ 55,194 $ (1,181 ) $ 83,152 $ (47,493 ) $ 181,254 Earnings from operations $ 8,251 $ 2,062 $ 1,589 $ 2,688 $ — $ 6,339 $ — $ 14,590 Interest expense — — — — — — (1,267 ) (1,267 ) Earnings before income taxes $ 8,251 $ 2,062 $ 1,589 $ 2,688 $ — $ 6,339 $ (1,267 ) $ 13,323 Nine Months Ended September 30, 2018 Revenues - unaffiliated customers: Premiums $ 130,361 $ 2,794 $ — $ — $ — $ 2,794 $ — $ 133,155 Products — 37 72 20,941 — 21,050 — 21,050 Services 6,248 3,587 2,306 449 — 6,342 — 12,590 Total revenues - unaffiliated customers 136,609 6,418 2,378 21,390 — 30,186 — 166,795 Total revenues - affiliated customers — 10,979 4,115 29,062 (1,026 ) 43,130 (43,130 ) — Investment and other income 633 355 15 32 — 402 — 1,035 Total revenues $ 137,242 $ 17,752 $ 6,508 $ 50,484 $ (1,026 ) $ 73,718 $ (43,130 ) $ 167,830 Earnings from operations $ 7,316 $ 1,680 $ 1,382 $ 2,469 $ — $ 5,531 $ — $ 12,847 Interest expense — — — — — — (1,026 ) (1,026 ) Earnings before income taxes $ 7,316 $ 1,680 $ 1,382 $ 2,469 $ — $ 5,531 $ (1,026 ) $ 11,821

Basis of Presentation Basis of

Basis of Presentation Basis of Presentation (Policies)	9 Months Ended
	Sep. 30, 2019
Basis of presentation [Abstract]
Basis of Accounting, Policy [Policy Text Block]	The Company has prepared the Condensed Consolidated Financial Statements according to U.S. Generally Accepted Accounting Principles (GAAP) and has included the accounts of UnitedHealth Group and its subsidiaries. The year-end condensed consolidated balance sheet was derived from audited financial statements, but does not include all disclosures required by GAAP. In accordance with the rules and regulations of the U.S. Securities and Exchange Commission (SEC), the Company has omitted certain footnote disclosures that would substantially duplicate the disclosures contained in its annual audited Consolidated Financial Statements. Therefore, these Condensed Consolidated Financial Statements should be read together with the Consolidated Financial Statements and the Notes included in Part II, Item 8, “Financial Statements and Supplementary Data” in the Company’s Annual Report on Form 10-K for the year ended December 31, 2018 as filed with the SEC ( 2018 10-K). The accompanying Condensed Consolidated Financial Statements include all normal recurring adjustments necessary to present the interim financial statements fairly.
Use of Estimates, Policy [Policy Text Block]	Use of Estimates These Condensed Consolidated Financial Statements include certain amounts based on the Company’s best estimates and judgments. The Company’s most significant estimates include medical costs payable and goodwill. Certain of these estimates require the application of complex assumptions and judgments, often because they involve matters that are inherently uncertain and will likely change in subsequent periods. The impact of any change in estimates is included in earnings in the period in which the estimate is adjusted.
Lessee, Leases [Policy Text Block]	The Company leases facilities and equipment under long-term operating leases that are non-cancelable and expire on various dates. At the lease commencement date, lease ROU assets and lease liabilities are recognized based on the present value of the future minimum lease payments over the lease term, which includes all fixed obligations arising from the lease contract. If an interest rate is not implicit in a lease, the Company utilizes its incremental borrowing rate for a period that closely matches the lease term.
New Accounting Pronouncements, Policy [Policy Text Block]	Recently Adopted Accounting Standards In February 2016, the Financial Accounting Standards Board (FASB) issued Accounting Standard Update (ASU) No. 2016-02, “Leases (Topic 842)” as modified by ASUs 2018-01, 2018-10, 2018-11, 2018-20 and 2019-01 (collectively, ASU 2016-02). Under ASU 2016-02, an entity is required to recognize assets and liabilities for the rights and obligations created by leases on the entity’s balance sheet for both finance and operating leases. The Company adopted ASU 2016-02 using a cumulative-effect upon adoption approach as of January 1, 2019. Upon adoption, the Company recognized $3.3 billion of lease right-of-use (ROU) assets and liabilities for operating leases on its Condensed Consolidated Balance Sheet, of which, $668 million were classified as current liabilities. The adoption of ASU 2016-02 was immaterial to the Company’s consolidated results of operations, equity and cash flows. The Company has included the disclosures required by ASU 2016-02 below and in Note 7, “Commitments and Contingencies.” The Company leases facilities and equipment under long-term operating leases that are non-cancelable and expire on various dates. At the lease commencement date, lease ROU assets and lease liabilities are recognized based on the present value of the future minimum lease payments over the lease term, which includes all fixed obligations arising from the lease contract. If an interest rate is not implicit in a lease, the Company utilizes its incremental borrowing rate for a period that closely matches the lease term. The Company’s ROU assets are included in other assets, and lease liabilities are included in other current liabilities and other liabilities in the Company’s Condensed Consolidated Balance Sheet. The Company has determined that there have been no other recently adopted or issued accounting standards that had, or will have, a material impact on its Condensed Consolidated Financial Statements.

Investments (Policies)

Investments (Policies)	9 Months Ended
	Sep. 30, 2019
Investment [Line Items]
Investment, Policy [Policy Text Block]	At each reporting period, the Company evaluates securities for impairment when the fair value of the investment is less than its amortized cost. The Company evaluated the underlying credit quality and credit ratings of the issuers, noting no significant deterioration since purchase. As of September 30, 2019 , the Company did not have the intent to sell any of the securities in an unrealized loss position. Therefore, the Company believes these losses to be temporary.

Investments (Tables)

Investments (Tables)	9 Months Ended
	Sep. 30, 2019
Short-Term and Long-Term Investments [Table Text Block]	A summary of debt securities by major security type is as follows: (in millions) Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value September 30, 2019 Debt securities - available-for-sale: U.S. government and agency obligations $ 3,591 $ 83 $ (2 ) $ 3,672 State and municipal obligations 5,657 256 (3 ) 5,910 Corporate obligations 17,824 352 (9 ) 18,167 U.S. agency mortgage-backed securities 6,361 113 (6 ) 6,468 Non-U.S. agency mortgage-backed securities 1,685 48 (1 ) 1,732 Total debt securities - available-for-sale 35,118 852 (21 ) 35,949 Debt securities - held-to-maturity: U.S. government and agency obligations 272 2 — 274 State and municipal obligations 32 1 — 33 Corporate obligations 547 — — 547 Total debt securities - held-to-maturity 851 3 — 854 Total debt securities $ 35,969 $ 855 $ (21 ) $ 36,803 December 31, 2018 Debt securities - available-for-sale: U.S. government and agency obligations $ 3,434 $ 13 $ (42 ) $ 3,405 State and municipal obligations 7,117 61 (57 ) 7,121 Corporate obligations 15,366 14 (218 ) 15,162 U.S. agency mortgage-backed securities 4,947 11 (106 ) 4,852 Non-U.S. agency mortgage-backed securities 1,376 2 (20 ) 1,358 Total debt securities - available-for-sale 32,240 101 (443 ) 31,898 Debt securities - held-to-maturity: U.S. government and agency obligations 255 1 (2 ) 254 State and municipal obligations 11 — — 11 Corporate obligations 355 — — 355 Total debt securities - held-to-maturity 621 1 (2 ) 620 Total debt securities $ 32,861 $ 102 $ (445 ) $ 32,518
Investments by Contractual Maturity [Table Text Block]	The amortized cost and fair value of debt securities as of September 30, 2019 , by contractual maturity, were as follows: Available-for-Sale Held-to-Maturity (in millions) Amortized Cost Fair Value Amortized Fair Due in one year or less $ 3,571 $ 3,577 $ 313 $ 313 Due after one year through five years 11,904 12,084 258 259 Due after five years through ten years 8,303 8,669 141 141 Due after ten years 3,294 3,419 139 141 U.S. agency mortgage-backed securities 6,361 6,468 — — Non-U.S. agency mortgage-backed securities 1,685 1,732 — — Total debt securities $ 35,118 $ 35,949 $ 851 $ 854
Fair Value of Available-for-Sale Investments with Gross Unrealized Losses by Investment Type and Length of Time that Individual Securities have been in a Continuous Unrealized Loss Position [Table Text Block]	The fair value of available-for-sale debt securities with gross unrealized losses by security type and length of time that individual securities have been in a continuous unrealized loss position were as follows: Less Than 12 Months 12 Months or Greater Total (in millions) Fair Value Gross Unrealized Losses Fair Value Gross Fair Value Gross September 30, 2019 Debt securities - available-for-sale: U.S. government and agency obligations $ 286 $ (1 ) $ 228 $ (1 ) $ 514 $ (2 ) State and municipal obligations 296 (2 ) 83 (1 ) 379 (3 ) Corporate obligations 1,360 (5 ) 1,022 (4 ) 2,382 (9 ) U.S. agency mortgage-backed securities 570 (2 ) 518 (4 ) 1,088 (6 ) Non-U.S. agency mortgage-backed securities 217 (1 ) — — 217 (1 ) Total debt securities - available-for-sale $ 2,729 $ (11 ) $ 1,851 $ (10 ) $ 4,580 $ (21 ) December 31, 2018 Debt securities - available-for-sale: U.S. government and agency obligations $ 998 $ (7 ) $ 1,425 $ (35 ) $ 2,423 $ (42 ) State and municipal obligations 1,334 (11 ) 2,491 (46 ) 3,825 (57 ) Corporate obligations 8,105 (109 ) 4,239 (109 ) 12,344 (218 ) U.S. agency mortgage-backed securities 1,296 (22 ) 2,388 (84 ) 3,684 (106 ) Non-U.S. agency mortgage-backed securities 622 (7 ) 459 (13 ) 1,081 (20 ) Total debt securities - available-for-sale $ 12,355 $ (156 ) $ 11,002 $ (287 ) $ 23,357 $ (443 )

Fair Value (Tables)

Fair Value (Tables)	9 Months Ended
	Sep. 30, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial Assets and Liabilities, Measured at Fair Value Recurring Basis [Table Text Block]	The following table presents a summary of fair value measurements by level and carrying values for items measured at fair value on a recurring basis in the Condensed Consolidated Balance Sheets: (in millions) Quoted Prices in Active Markets (Level 1) Other Observable Inputs (Level 2) Unobservable Inputs (Level 3) Total Fair and Carrying Value September 30, 2019 Cash and cash equivalents $ 12,210 $ 153 $ — $ 12,363 Debt securities - available-for-sale: U.S. government and agency obligations 3,421 251 — 3,672 State and municipal obligations — 5,910 — 5,910 Corporate obligations 71 17,879 217 18,167 U.S. agency mortgage-backed securities — 6,468 — 6,468 Non-U.S. agency mortgage-backed securities — 1,732 — 1,732 Total debt securities - available-for-sale 3,492 32,240 217 35,949 Equity securities 1,839 21 — 1,860 Assets under management 1,116 1,907 28 3,051 Total assets at fair value $ 18,657 $ 34,321 $ 245 $ 53,223 Percentage of total assets at fair value 35 % 65 % — % 100 % December 31, 2018 Cash and cash equivalents $ 10,757 $ 109 $ — $ 10,866 Debt securities - available-for-sale: U.S. government and agency obligations 3,060 345 — 3,405 State and municipal obligations — 7,121 — 7,121 Corporate obligations 39 14,950 173 15,162 U.S. agency mortgage-backed securities — 4,852 — 4,852 Non-U.S. agency mortgage-backed securities — 1,358 — 1,358 Total debt securities - available-for-sale 3,099 28,626 173 31,898 Equity securities 1,832 13 — 1,845 Assets under management 1,086 1,938 8 3,032 Total assets at fair value $ 16,774 $ 30,686 $ 181 $ 47,641 Percentage of total assets at fair value 35 % 65 % — % 100 %
Fair Value Measurements, Nonrecurring [Table Text Block]	The following table presents a summary of fair value measurements by level and carrying values for certain financial instruments not measured at fair value on a recurring basis in the Condensed Consolidated Balance Sheets: (in millions) Quoted Prices in Active Markets (Level 1) Other Observable Inputs (Level 2) Unobservable Inputs (Level 3) Total Fair Value Total Carrying Value September 30, 2019 Debt securities - held-to-maturity $ 410 $ 176 $ 268 $ 854 $ 851 Long-term debt and other financing obligations $ — $ 45,342 $ — $ 45,342 $ 40,814 December 31, 2018 Debt securities - held-to-maturity $ 260 $ 65 $ 295 $ 620 $ 621 Long-term debt and other financing obligations $ — $ 37,944 $ — $ 37,944 $ 36,554

Medical Costs Payable (Tables)

Medical Costs Payable (Tables)	9 Months Ended
	Sep. 30, 2019
Insurance [Abstract]
Schedule of Liability for Unpaid Claims and Claims Adjustment Expense [Table Text Block]	The following table shows the components of the change in medical costs payable for the nine months ended September 30: (in millions) 2019 2018 Medical costs payable, beginning of period $ 19,891 $ 17,871 Acquisitions 868 333 Reported medical costs: Current year 117,624 108,658 Prior years (460 ) (210 ) Total reported medical costs 117,164 108,448 Medical payments: Payments for current year (99,487 ) (90,348 ) Payments for prior years (17,497 ) (16,454 ) Total medical payments (116,984 ) (106,802 ) Medical costs payable, end of period $ 20,939 $ 19,850

Commercial Paper and Long-Ter_2

Commercial Paper and Long-Term Debt (Tables)	9 Months Ended
	Sep. 30, 2019
Debt Instrument [Line Items]
Commercial Paper and Long-Term Debt [Table Text Block]	Commercial paper and senior unsecured long-term debt consisted of the following: September 30, 2019 December 31, 2018 (in millions, except percentages) Par Value Carrying Value Fair Value Par Value Carrying Value Fair Value Commercial paper $ 4,082 $ 4,080 $ 4,080 $ — $ — $ — 1.700% notes due February 2019 — — — 750 750 749 1.625% notes due March 2019 — — — 500 500 499 2.300% notes due December 2019 500 499 500 500 494 497 2.700% notes due July 2020 1,500 1,499 1,508 1,500 1,498 1,494 Floating rate notes due October 2020 300 300 300 300 299 298 3.875% notes due October 2020 450 450 457 450 443 456 1.950% notes due October 2020 900 898 900 900 897 884 4.700% notes due February 2021 400 404 412 400 398 412 2.125% notes due March 2021 750 748 752 750 747 734 Floating rate notes due June 2021 350 349 349 350 349 347 3.150% notes due June 2021 400 399 408 400 399 400 3.375% notes due November 2021 500 502 512 500 489 503 2.875% notes due December 2021 750 755 764 750 735 748 2.875% notes due March 2022 1,100 1,088 1,120 1,100 1,051 1,091 3.350% notes due July 2022 1,000 997 1,036 1,000 997 1,005 2.375% notes due October 2022 900 895 909 900 894 872 0.000% notes due November 2022 15 13 13 15 12 13 2.750% notes due February 2023 625 627 637 625 602 611 2.875% notes due March 2023 750 776 769 750 750 739 3.500% notes due June 2023 750 747 786 750 746 756 3.500% notes due February 2024 750 745 790 750 745 755 2.375% notes due August 2024 750 746 756 — — — 3.750% notes due July 2025 2,000 1,990 2,150 2,000 1,989 2,025 3.700% notes due December 2025 300 298 323 300 298 303 3.100% notes due March 2026 1,000 996 1,045 1,000 995 965 3.450% notes due January 2027 750 746 798 750 746 742 3.375% notes due April 2027 625 619 663 625 619 611 2.950% notes due October 2027 950 939 982 950 938 898 3.850% notes due June 2028 1,150 1,142 1,259 1,150 1,142 1,163 3.875% notes due December 2028 850 843 936 850 842 861 2.875% notes due August 2029 1,000 1,022 1,021 — — — 4.625% notes due July 2035 1,000 992 1,208 1,000 992 1,060 5.800% notes due March 2036 850 838 1,134 850 838 1,003 6.500% notes due June 2037 500 492 711 500 492 638 6.625% notes due November 2037 650 641 940 650 641 841 6.875% notes due February 2038 1,100 1,076 1,625 1,100 1,076 1,437 3.500% notes due August 2039 1,250 1,241 1,301 — — — 5.700% notes due October 2040 300 296 397 300 296 355 5.950% notes due February 2041 350 345 476 350 345 426 4.625% notes due November 2041 600 589 710 600 588 627 4.375% notes due March 2042 502 484 572 502 484 503 3.950% notes due October 2042 625 607 676 625 607 596 4.250% notes due March 2043 750 735 844 750 734 744 4.750% notes due July 2045 2,000 1,973 2,431 2,000 1,973 2,116 4.200% notes due January 2047 750 738 852 750 738 745 4.250% notes due April 2047 725 717 823 725 717 719 3.750% notes due October 2047 950 933 1,005 950 933 869 4.250% notes due June 2048 1,350 1,329 1,550 1,350 1,329 1,349 4.450% notes due December 2048 1,100 1,086 1,301 1,100 1,087 1,132 3.700% notes due August 2049 1,250 1,235 1,323 — — — 3.875% notes due August 2059 1,250 1,231 1,327 — — — Total commercial paper and long-term debt $ 43,999 $ 43,690 $ 48,141 $ 35,667 $ 35,234 $ 36,591

Dividends (Tables)

Dividends (Tables)	9 Months Ended
	Sep. 30, 2019
Class of Stock [Line Items]
Dividends Declared [Table Text Block]	The following table provides details of the Company’s 2019 dividend payments: Payment Date Amount per Share Total Amount Paid (in millions) March 19 $ 0.90 $ 860 June 25 1.08 1,024 September 24 1.08 1,024

Commitments and Contingencies_2

Commitments and Contingencies (Tables)	9 Months Ended
	Sep. 30, 2019
Commitments and Contingencies Disclosure [Abstract]
Lessee, Operating Lease, Liability, Maturity [Table Text Block]	As of September 30, 2019 , future minimum annual lease payments under all non-cancelable operating leases were as follows: (in millions) Future Operating Lease Payments 2019 $ 198 2020 782 2021 693 2022 580 2023 477 Thereafter 1,978 Total future minimum lease payments 4,708 Less imputed interest (758 ) Total $ 3,950

Business Combinations (Tables)

Business Combinations (Tables)	9 Months Ended
	Sep. 30, 2019
Business Combinations [Abstract]
Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Table Text Block]	Acquired tangible assets (liabilities) at acquisition date were: (in millions) Cash and cash equivalents $ 1,537 Accounts receivable and other current assets 1,775 Property, equipment and other long-term assets 1,941 Medical costs payable (868 ) Accounts payable and other current liabilities (1,669 ) Other long-term liabilities (1,283 ) Total net tangible assets $ 1,433
Schedule of Finite-Lived Intangible Assets Acquired as Part of Business Combination [Table Text Block]	The acquisition date fair values and weighted-average useful lives assigned to acquired finite-lived intangible assets were: (in millions, except years) Fair Value Weighted-Average Useful Life Customer-related $ 1,670 14 Trademarks and technology 117 4 Other 164 10 Total acquired finite-lived intangible assets $ 1,951 13

Segment Financial Information_2

Segment Financial Information (Tables)	9 Months Ended
	Sep. 30, 2019
Segment Reporting [Abstract]
Segment Financial Information [Table Text Block]	The following tables present reportable segment financial information: Optum (in millions) UnitedHealthcare OptumHealth OptumInsight OptumRx Optum Eliminations Optum Corporate and Eliminations Consolidated Three Months Ended September 30, 2019 Revenues - unaffiliated customers: Premiums $ 45,557 $ 1,840 $ — $ — $ — $ 1,840 $ — $ 47,397 Products — 6 29 7,511 — 7,546 — 7,546 Services 2,274 1,487 988 193 — 2,668 — 4,942 Total revenues - unaffiliated customers 47,831 3,333 1,017 7,704 — 12,054 — 59,885 Total revenues - affiliated customers — 4,630 1,594 10,734 (441 ) 16,517 (16,517 ) — Investment and other income 274 170 6 16 — 192 — 466 Total revenues $ 48,105 $ 8,133 $ 2,617 $ 18,454 $ (441 ) $ 28,763 $ (16,517 ) $ 60,351 Earnings from operations $ 2,655 $ 748 $ 632 $ 979 $ — $ 2,359 $ — $ 5,014 Interest expense — — — — — — (449 ) (449 ) Earnings before income taxes $ 2,655 $ 748 $ 632 $ 979 $ — $ 2,359 $ (449 ) $ 4,565 Three Months Ended September 30, 2018 Revenues - unaffiliated customers: Premiums $ 43,628 $ 985 $ — $ — $ — $ 985 $ — $ 44,613 Products — 13 29 7,302 — 7,344 — 7,344 Services 2,067 1,196 790 164 — 2,150 — 4,217 Total revenues - unaffiliated customers 45,695 2,194 819 7,466 — 10,479 — 56,174 Total revenues - affiliated customers — 3,733 1,431 9,960 (352 ) 14,772 (14,772 ) — Investment and other income 242 125 4 11 — 140 — 382 Total revenues $ 45,937 $ 6,052 $ 2,254 $ 17,437 $ (352 ) $ 25,391 $ (14,772 ) $ 56,556 Earnings from operations $ 2,559 $ 622 $ 534 $ 875 $ — $ 2,031 $ — $ 4,590 Interest expense — — — — — — (353 ) (353 ) Earnings before income taxes $ 2,559 $ 622 $ 534 $ 875 $ — $ 2,031 $ (353 ) $ 4,237 Optum (in millions) UnitedHealthcare OptumHealth OptumInsight OptumRx Optum Eliminations Optum Corporate and Consolidated Nine Months Ended September 30, 2019 Revenues - unaffiliated customers: Premiums $ 138,088 $ 3,986 $ — $ — $ — $ 3,986 $ — $ 142,074 Products — 23 74 23,874 — 23,971 — 23,971 Services 6,603 4,131 2,532 490 — 7,153 — 13,756 Total revenues - unaffiliated customers 144,691 8,140 2,606 24,364 — 35,110 — 179,801 Total revenues - affiliated customers — 13,366 4,522 30,786 (1,181 ) 47,493 (47,493 ) — Investment and other income 904 488 17 44 — 549 — 1,453 Total revenues $ 145,595 $ 21,994 $ 7,145 $ 55,194 $ (1,181 ) $ 83,152 $ (47,493 ) $ 181,254 Earnings from operations $ 8,251 $ 2,062 $ 1,589 $ 2,688 $ — $ 6,339 $ — $ 14,590 Interest expense — — — — — — (1,267 ) (1,267 ) Earnings before income taxes $ 8,251 $ 2,062 $ 1,589 $ 2,688 $ — $ 6,339 $ (1,267 ) $ 13,323 Nine Months Ended September 30, 2018 Revenues - unaffiliated customers: Premiums $ 130,361 $ 2,794 $ — $ — $ — $ 2,794 $ — $ 133,155 Products — 37 72 20,941 — 21,050 — 21,050 Services 6,248 3,587 2,306 449 — 6,342 — 12,590 Total revenues - unaffiliated customers 136,609 6,418 2,378 21,390 — 30,186 — 166,795 Total revenues - affiliated customers — 10,979 4,115 29,062 (1,026 ) 43,130 (43,130 ) — Investment and other income 633 355 15 32 — 402 — 1,035 Total revenues $ 137,242 $ 17,752 $ 6,508 $ 50,484 $ (1,026 ) $ 73,718 $ (43,130 ) $ 167,830 Earnings from operations $ 7,316 $ 1,680 $ 1,382 $ 2,469 $ — $ 5,531 $ — $ 12,847 Interest expense — — — — — — (1,026 ) (1,026 ) Earnings before income taxes $ 7,316 $ 1,680 $ 1,382 $ 2,469 $ — $ 5,531 $ (1,026 ) $ 11,821

Basis of Presentation Basis o_2

Basis of Presentation Basis of Presentation, Uses of Estimates and Significant Accounting Policies (Details) - Accounting Standards Update 2016-02 [Member] - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2019	Jan. 01, 2019
Change in Accounting Principle, Accounting Standards Update, Transition Option Elected [Fixed List]		Modified Retrospective
New Accounting Pronouncement, Transition Guidance Not Significant or Not Practical	Impact is not material
Operating Lease, Right-of-Use Asset		$ 3,300
Operating Lease, Liability, Current		$ 668

Investments (Narrative) (Detail

Investments (Narrative) (Details) number in Thousands, $ in Billions	Sep. 30, 2019USD ($)	Dec. 31, 2018USD ($)
Investment [Line Items]
Equity Securities, FV-NI and without Readily Determinable Fair Value	$ 2	$ 2
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	4
Total number of security positions	32
Equity Method Investments	$ 1.4	$ 1.5

Investments (Short-Term and Lon

Investments (Short-Term and Long-Term Investments) (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Amortized Cost	$ 35,118	$ 32,240
Securities, Available for sale Debt Securities, Gross Unrealized Gains	852	101
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(21)	(443)
Debt Securities, Available-for-sale	35,949	31,898
Held-to-maturity securities, Amortized Cost	851	621
Securities, Held to maturity, Unrecognized Holding Gain	3	1
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	0	(2)
Debt Securities, Held-to-maturity, Fair Value	854	620
Total debt securities, Amortized Cost	35,969	32,861
Total debt securities, Gross Unrealized Gains	855	102
Total debt securities, Gross Unrealized Losses	(21)	(445)
Debt securities, Fair Value Disclosure	36,803	32,518
Debt Securities [Member]
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale	35,949	31,898
U.S. Government and Agency Obligations [Member]
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Amortized Cost	3,591	3,434
Securities, Available for sale Debt Securities, Gross Unrealized Gains	83	13
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(2)	(42)
Debt Securities, Available-for-sale	3,672	3,405
Held-to-maturity securities, Amortized Cost	272	255
Securities, Held to maturity, Unrecognized Holding Gain	2	1
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	0	(2)
Debt Securities, Held-to-maturity, Fair Value	274	254
State and Municipal Obligations [Member]
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Amortized Cost	5,657	7,117
Securities, Available for sale Debt Securities, Gross Unrealized Gains	256	61
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(3)	(57)
Debt Securities, Available-for-sale	5,910	7,121
Held-to-maturity securities, Amortized Cost	32	11
Securities, Held to maturity, Unrecognized Holding Gain	1	0
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	0	0
Debt Securities, Held-to-maturity, Fair Value	33	11
Corporate Obligations [Member]
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Amortized Cost	17,824	15,366
Securities, Available for sale Debt Securities, Gross Unrealized Gains	352	14
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(9)	(218)
Debt Securities, Available-for-sale	18,167	15,162
Held-to-maturity securities, Amortized Cost	547	355
Securities, Held to maturity, Unrecognized Holding Gain	0	0
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	0	0
Debt Securities, Held-to-maturity, Fair Value	547	355
U.S. Agency Mortgage-Backed Securities [Member]
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Amortized Cost	6,361	4,947
Securities, Available for sale Debt Securities, Gross Unrealized Gains	113	11
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(6)	(106)
Debt Securities, Available-for-sale	6,468	4,852
Non-U.S. Agency Mortgage-Backed Securities [Member]
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Amortized Cost	1,685	1,376
Securities, Available for sale Debt Securities, Gross Unrealized Gains	48	2
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(1)	(20)
Debt Securities, Available-for-sale	$ 1,732	$ 1,358

Investments (Amortized Cost and

Investments (Amortized Cost and Fair Value of Available-for-Sale Debt Securities by Contractual Maturity) (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Schedule of Investments [Line Items]
Due in one year or less, Amortized Cost	$ 3,571
Due after one year through five years, Amortized Cost	11,904
Due after five years through ten years, Amortized Cost	8,303
Due after ten years, Amortized Cost	3,294
Total debt securities - available-for-sale, Amortized Cost	35,118	$ 32,240
Due in one year or less, Fair Value	3,577
Due after one year through five years, Fair Value	12,084
Due after five years through ten years, Fair Value	8,669
Due after ten years, Fair Value	3,419
Debt Securities, Available-for-sale	35,949	31,898
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, within One Year, Amortized Cost	313
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Amortized Cost	258
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Amortized Cost	141
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, after 10 Years, Amortized Cost	139
Debt Securities, Held-to-maturity	851	621
Held-to-maturity Securities, Debt Maturities, within One Year, Fair Value	313
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Fair Value	259
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Fair Value	141
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, after 10 Years, Fair Value	141
Debt Securities, Held-to-maturity, Fair Value	854	620
U.S. Agency Mortgage-Backed Securities [Member]
Schedule of Investments [Line Items]
Mortgage-backed securities, Amortized Cost	6,361
Total debt securities - available-for-sale, Amortized Cost	6,361	4,947
Mortgage-backed securities, Fair Value	6,468
Debt Securities, Available-for-sale	6,468	4,852
Non-U.S. Agency Mortgage-Backed Securities [Member]
Schedule of Investments [Line Items]
Mortgage-backed securities, Amortized Cost	1,685
Total debt securities - available-for-sale, Amortized Cost	1,685	1,376
Mortgage-backed securities, Fair Value	1,732
Debt Securities, Available-for-sale	$ 1,732	$ 1,358

Investments (Fair Value of Avai

Investments (Fair Value of Available-For-Sale Investments with Gross Unrealized Losses by Investment Type and Length of Time That Individual Securities Have Been in a Continuous Unrealized Loss Position) (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Debt Securities [Member]
Schedule of Investments [Line Items]
Less Than 12 Months, Fair Value	$ 2,729	$ 12,355
Less Than 12 Months, Gross Unrealized Losses	(11)	(156)
Greater Than 12 Months, Fair Value	1,851	11,002
Greater Than 12 Months, Gross Unrealized Losses	(10)	(287)
Total, Fair Value	4,580	23,357
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	(21)	(443)
U.S. Government and Agency Obligations [Member]
Schedule of Investments [Line Items]
Less Than 12 Months, Fair Value	286	998
Less Than 12 Months, Gross Unrealized Losses	(1)	(7)
Greater Than 12 Months, Fair Value	228	1,425
Greater Than 12 Months, Gross Unrealized Losses	(1)	(35)
Total, Fair Value	514	2,423
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	(2)	(42)
State and Municipal Obligations [Member]
Schedule of Investments [Line Items]
Less Than 12 Months, Fair Value	296	1,334
Less Than 12 Months, Gross Unrealized Losses	(2)	(11)
Greater Than 12 Months, Fair Value	83	2,491
Greater Than 12 Months, Gross Unrealized Losses	(1)	(46)
Total, Fair Value	379	3,825
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	(3)	(57)
Corporate Obligations [Member]
Schedule of Investments [Line Items]
Less Than 12 Months, Fair Value	1,360	8,105
Less Than 12 Months, Gross Unrealized Losses	(5)	(109)
Greater Than 12 Months, Fair Value	1,022	4,239
Greater Than 12 Months, Gross Unrealized Losses	(4)	(109)
Total, Fair Value	2,382	12,344
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	(9)	(218)
U.S. Agency Mortgage-Backed Securities [Member]
Schedule of Investments [Line Items]
Less Than 12 Months, Fair Value	570	1,296
Less Than 12 Months, Gross Unrealized Losses	(2)	(22)
Greater Than 12 Months, Fair Value	518	2,388
Greater Than 12 Months, Gross Unrealized Losses	(4)	(84)
Total, Fair Value	1,088	3,684
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	(6)	(106)
Non-U.S. Agency Mortgage-Backed Securities [Member]
Schedule of Investments [Line Items]
Less Than 12 Months, Fair Value	217	622
Less Than 12 Months, Gross Unrealized Losses	(1)	(7)
Greater Than 12 Months, Fair Value	0	459
Greater Than 12 Months, Gross Unrealized Losses	0	(13)
Total, Fair Value	217	1,081
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	$ (1)	$ (20)

Fair Value (Narrative) (Details

Fair Value (Narrative) (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Fair Value [Line Items]
Transfers Into Level 3	$ 0	$ 0
Transfers out of Level 3	0	0
Fair Value, Nonrecurring [Member]
Fair Value [Line Items]
Significant fair value adjustments for assets and liabilities measured on a nonrecurring basis	$ 0	$ 0

Fair Value (Financial Assets an

Fair Value (Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis) (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	$ 12,363	$ 10,866
Debt Securities, Available-for-sale	35,949	31,898
Equity Securities, Fair Value	1,860	1,845
Assets under management	3,051	3,032
Assets, Fair Value Disclosure	53,223	47,641
Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	35,949	31,898
U.S. Government and Agency Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	3,672	3,405
State and Municipal Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	5,910	7,121
Corporate Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	18,167	15,162
U.S. Agency Mortgage-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	6,468	4,852
Non-U.S. Agency Mortgage-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	1,732	1,358
Quoted Prices in Active Markets (Level 1) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	12,210	10,757
Equity Securities, Fair Value	1,839	1,832
Assets under management	1,116	1,086
Assets, Fair Value Disclosure	18,657	16,774
Quoted Prices in Active Markets (Level 1) [Member] | Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	3,492	3,099
Quoted Prices in Active Markets (Level 1) [Member] | U.S. Government and Agency Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	3,421	3,060
Quoted Prices in Active Markets (Level 1) [Member] | State and Municipal Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	0	0
Quoted Prices in Active Markets (Level 1) [Member] | Corporate Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	71	39
Quoted Prices in Active Markets (Level 1) [Member] | U.S. Agency Mortgage-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	0	0
Quoted Prices in Active Markets (Level 1) [Member] | Non-U.S. Agency Mortgage-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	0	0
Other Observable Inputs (Level 2) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	153	109
Equity Securities, Fair Value	21	13
Assets under management	1,907	1,938
Assets, Fair Value Disclosure	34,321	30,686
Other Observable Inputs (Level 2) [Member] | Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	32,240	28,626
Other Observable Inputs (Level 2) [Member] | U.S. Government and Agency Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	251	345
Other Observable Inputs (Level 2) [Member] | State and Municipal Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	5,910	7,121
Other Observable Inputs (Level 2) [Member] | Corporate Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	17,879	14,950
Other Observable Inputs (Level 2) [Member] | U.S. Agency Mortgage-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	6,468	4,852
Other Observable Inputs (Level 2) [Member] | Non-U.S. Agency Mortgage-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	1,732	1,358
Unobservable Inputs (Level 3) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	0	0
Equity Securities, Fair Value	0	0
Assets under management	28	8
Assets, Fair Value Disclosure	245	181
Unobservable Inputs (Level 3) [Member] | Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	217	173
Unobservable Inputs (Level 3) [Member] | U.S. Government and Agency Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	0	0
Unobservable Inputs (Level 3) [Member] | State and Municipal Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	0	0
Unobservable Inputs (Level 3) [Member] | Corporate Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	217	173
Unobservable Inputs (Level 3) [Member] | U.S. Agency Mortgage-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	0	0
Unobservable Inputs (Level 3) [Member] | Non-U.S. Agency Mortgage-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale	$ 0	$ 0

Fair Value (Financial Assets _2

Fair Value (Financial Assets and Liabilities, Not Measured at Fair Value on a Recurring Basis) (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Held-to-maturity, Fair Value	$ 854	$ 620
Debt Securities, Held-to-maturity	851	621
Debt and other financing obligations, carrying value	43,690	35,234
Fair Value, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Held-to-maturity, Fair Value	854	620
Debt and other financing obligations	45,342	37,944
Fair Value, Nonrecurring [Member] | Quoted Prices in Active Markets (Level 1) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Held-to-maturity, Fair Value	410	260
Debt and other financing obligations	0	0
Fair Value, Nonrecurring [Member] | Other Observable Inputs (Level 2) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Held-to-maturity, Fair Value	176	65
Debt and other financing obligations	45,342	37,944
Fair Value, Nonrecurring [Member] | Unobservable Inputs (Level 3) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Held-to-maturity, Fair Value	268	295
Debt and other financing obligations	0	0
Long-term debt and other financing obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt and other financing obligations, carrying value	$ 40,814	$ 36,554

Medical Costs Payable (Narrativ

Medical Costs Payable (Narrative) (Details) - USD ($) $ in Billions	Sep. 30, 2019	Dec. 31, 2018
Liability for Claims and Claims Adjustment Expense [Line Items]
Liability for Unpaid Claims and Claims Adjustment Expense, Incurred but Not Reported (IBNR) Claims, Amount	$ 14.2	$ 13.2

Medical Costs Payable Rollforwa

Medical Costs Payable Rollforward (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items]
Medical costs payable, beginning of period	$ 19,891	$ 17,871
Acquisitions	868	333
Reported medical costs:
Current year	117,624	108,658
Prior years	(460)	(210)
Total reported medical costs	117,164	108,448
Medical payments:
Payments for current year	(99,487)	(90,348)
Payments for prior years	(17,497)	(16,454)
Total medical payments	(116,984)	(106,802)
Medical costs payable, end of period	$ 20,939	$ 19,850

Commercial Paper and Long-Ter_3

Commercial Paper and Long-Term Debt (Narrative) (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2019	Dec. 31, 2018
Minimum [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Interest Rate at Period End	2.70%
Maximum [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Interest Rate at Period End	2.80%
Five Year $3.5 Billion Credit Facility [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Long-term Line of Credit	$ 0
Line of Credit, Credit Facility, Maximum Borrowing Capacity	$ 3,500
Line of Credit Facility, Expiration Period	5 years
Three Year $3.5 Billion Credit Facility [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Long-term Line of Credit	$ 0
Line of Credit, Credit Facility, Maximum Borrowing Capacity	$ 3,500
Line of Credit Facility, Expiration Period	3 years
364 Day $3.0 Billion Credit Facility [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of Credit, Current	$ 0
Line of Credit, Credit Facility, Maximum Borrowing Capacity	$ 3,000
Line of Credit Facility, Expiration Period	364 days
364 Day $2.5 Billion Credit Facility [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of Credit, Current	$ 0
Line of Credit, Credit Facility, Maximum Borrowing Capacity	$ 2,500
Line of Credit Facility, Expiration Period	364 days
Subsidiaries [Member]
Debt Instrument [Line Items]
Other Long-term Debt	$ 1,200	$ 1,300
Other Long-term Debt, Current	$ 309	$ 229
Commercial Paper [Member]
Debt Instrument [Line Items]
Short-term Debt, Weighted Average Interest Rate, at Point in Time	2.20%

Commercial Paper and Long-Ter_4

Commercial Paper and Long-Term Debt (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Par Value	$ 43,999	$ 35,667
Carrying value, Combined Amount	43,690	35,234
Fair Value	48,141	36,591
Commercial Paper [Member]
Debt Instrument [Line Items]
Par Value	4,082	0
Commercial Paper	4,080	0
Fair Value	$ 4,080	0
1.700% Notes due February 2019 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	1.70%
Par Value	$ 0	750
Carrying Value, Current	0	750
Fair Value	$ 0	749
1.625% notes due March 2019 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	1.625%
Par Value	$ 0	500
Carrying Value, Current	0	500
Fair Value	$ 0	499
2.300% notes due December 2019 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	2.30%
Par Value	$ 500	500
Carrying Value, Current	499	494
Fair Value	$ 500	497
2.700% Notes due July 2020 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	2.70%
Par Value	$ 1,500	1,500
Carrying Value, Noncurrent	1,499	1,498
Fair Value	1,508	1,494
Floating rate notes due October 2020 [Member]
Debt Instrument [Line Items]
Par Value	300	300
Carrying Value, Noncurrent	300	299
Fair Value	$ 300	298
3.875% notes due October 2020 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.875%
Par Value	$ 450	450
Carrying Value, Noncurrent	450	443
Fair Value	$ 457	456
1.950% notes due October 2020 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	1.95%
Par Value	$ 900	900
Carrying Value, Noncurrent	898	897
Fair Value	$ 900	884
4.700% notes due February 2021 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	4.70%
Par Value	$ 400	400
Carrying Value, Noncurrent	404	398
Fair Value	$ 412	412
2.125% notes due March 2021 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	2.125%
Par Value	$ 750	750
Carrying Value, Noncurrent	748	747
Fair Value	752	734
Floating rate notes due June 2021 [Member]
Debt Instrument [Line Items]
Par Value	350	350
Carrying Value, Noncurrent	349	349
Fair Value	$ 349	347
3.150% notes due June 2021 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.15%
Par Value	$ 400	400
Carrying Value, Noncurrent	399	399
Fair Value	$ 408	400
3.375% notes due November 2021 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.375%
Par Value	$ 500	500
Carrying Value, Noncurrent	502	489
Fair Value	$ 512	503
2.875% notes due December 2021 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	2.875%
Par Value	$ 750	750
Carrying Value, Noncurrent	755	735
Fair Value	$ 764	748
2.875% notes due March 2022 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	2.875%
Par Value	$ 1,100	1,100
Carrying Value, Noncurrent	1,088	1,051
Fair Value	$ 1,120	1,091
3.350% notes due July 2022 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.35%
Par Value	$ 1,000	1,000
Carrying Value, Noncurrent	997	997
Fair Value	$ 1,036	1,005
2.375% notes due October 2022 [Member] [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	2.375%
Par Value	$ 900	900
Carrying Value, Noncurrent	895	894
Fair Value	$ 909	872
Zero Coupon notes due November 2022 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	0.00%
Par Value	$ 15	15
Carrying Value, Noncurrent	13	12
Fair Value	$ 13	13
2.750% notes due February 2023 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	2.75%
Par Value	$ 625	625
Carrying Value, Noncurrent	627	602
Fair Value	$ 637	611
2.875% notes due March 2023 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	2.875%
Par Value	$ 750	750
Carrying Value, Noncurrent	776	750
Fair Value	$ 769	739
3.500% notes due June 2023 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.50%
Par Value	$ 750	750
Carrying Value, Noncurrent	747	746
Fair Value	$ 786	756
3.500% notes due February 2024 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.50%
Par Value	$ 750	750
Carrying Value, Noncurrent	745	745
Fair Value	$ 790	755
2.375% notes due August 2024 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	2.375%
Par Value	$ 750	0
Carrying Value, Noncurrent	746	0
Fair Value	$ 756	0
3.750% notes due July 2025 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.75%
Par Value	$ 2,000	2,000
Carrying Value, Noncurrent	1,990	1,989
Fair Value	$ 2,150	2,025
3.700% notes due December 2025 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.70%
Par Value	$ 300	300
Carrying Value, Noncurrent	298	298
Fair Value	$ 323	303
3.100% notes due March 2026 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.10%
Par Value	$ 1,000	1,000
Carrying Value, Noncurrent	996	995
Fair Value	$ 1,045	965
3.450% notes due January 2027 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.45%
Par Value	$ 750	750
Carrying Value, Noncurrent	746	746
Fair Value	$ 798	742
3.375% notes due April 2027 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.375%
Par Value	$ 625	625
Carrying Value, Noncurrent	619	619
Fair Value	$ 663	611
2.950% notes due October 2027 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	2.95%
Par Value	$ 950	950
Carrying Value, Noncurrent	939	938
Fair Value	$ 982	898
3.850% notes due June 2028 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.85%
Par Value	$ 1,150	1,150
Carrying Value, Noncurrent	1,142	1,142
Fair Value	$ 1,259	1,163
3.875% notes due December 2028 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.875%
Par Value	$ 850	850
Carrying Value, Noncurrent	843	842
Fair Value	$ 936	861
2.875% notes due August 2029 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	2.875%
Par Value	$ 1,000	0
Carrying Value, Noncurrent	1,022	0
Fair Value	$ 1,021	0
4.625% notes due July 2035 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	4.625%
Par Value	$ 1,000	1,000
Carrying Value, Noncurrent	992	992
Fair Value	$ 1,208	1,060
5.800% notes due March 2036 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	5.80%
Par Value	$ 850	850
Carrying Value, Noncurrent	838	838
Fair Value	$ 1,134	1,003
6.500% Notes Due June 2037 [Member] [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	6.50%
Par Value	$ 500	500
Carrying Value, Noncurrent	492	492
Fair Value	$ 711	638
6.625% Notes due November 2037 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	6.625%
Par Value	$ 650	650
Carrying Value, Noncurrent	641	641
Fair Value	$ 940	841
6.875% notes due February 2038 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	6.875%
Par Value	$ 1,100	1,100
Carrying Value, Noncurrent	1,076	1,076
Fair Value	$ 1,625	1,437
3.500% notes due August 2039 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.50%
Par Value	$ 1,250	0
Carrying Value, Noncurrent	1,241	0
Fair Value	$ 1,301	0
5.700% notes due October 2040 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	5.70%
Par Value	$ 300	300
Carrying Value, Noncurrent	296	296
Fair Value	$ 397	355
5.950% notes due February 2041 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	5.95%
Par Value	$ 350	350
Carrying Value, Noncurrent	345	345
Fair Value	$ 476	426
4.625% notes due November 2041 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	4.625%
Par Value	$ 600	600
Carrying Value, Noncurrent	589	588
Fair Value	$ 710	627
4.375% notes due March 2042 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	4.375%
Par Value	$ 502	502
Carrying Value, Noncurrent	484	484
Fair Value	$ 572	503
3.950% notes due October 2042 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.95%
Par Value	$ 625	625
Carrying Value, Noncurrent	607	607
Fair Value	$ 676	596
4.250% notes due March 2043 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	4.25%
Par Value	$ 750	750
Carrying Value, Noncurrent	735	734
Fair Value	$ 844	744
4.750% notes due July 2045 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	4.75%
Par Value	$ 2,000	2,000
Carrying Value, Noncurrent	1,973	1,973
Fair Value	$ 2,431	2,116
4.200% notes due January 2047 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	4.20%
Par Value	$ 750	750
Carrying Value, Noncurrent	738	738
Fair Value	$ 852	745
4.250% notes due April 2047 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	4.25%
Par Value	$ 725	725
Carrying Value, Noncurrent	717	717
Fair Value	$ 823	719
3.750% notes due October 2047 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.75%
Par Value	$ 950	950
Carrying Value, Noncurrent	933	933
Fair Value	$ 1,005	869
4.250% notes due June 2048 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	4.25%
Par Value	$ 1,350	1,350
Carrying Value, Noncurrent	1,329	1,329
Fair Value	$ 1,550	1,349
4.450% notes due December 2048 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	4.45%
Par Value	$ 1,100	1,100
Carrying Value, Noncurrent	1,086	1,087
Fair Value	$ 1,301	1,132
3.700% notes due August 2049 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.70%
Par Value	$ 1,250	0
Carrying Value, Noncurrent	1,235	0
Fair Value	$ 1,323	0
3.875% notes due August 2059 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.875%
Par Value	$ 1,250	0
Carrying Value, Noncurrent	1,231	0
Fair Value	$ 1,327	$ 0

Dividends (Details)

Dividends (Details) - USD ($) $ / shares in Units, $ in Millions	Sep. 24, 2019	Jun. 25, 2019	Mar. 19, 2019	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Class of Stock [Line Items]
Common Stock, Dividends, Per Share, Cash Paid	$ 1.08	$ 1.08	$ 0.90	$ 1.08	$ 0.90	$ 3.06	$ 2.55
Payments of Ordinary Dividends, Common Stock	$ 1,024	$ 1,024	$ 860			$ 2,908	$ 2,454

Commitments and Contingencies N

Commitments and Contingencies Narrative (Details) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2019USD ($)	Sep. 30, 2019USD ($)
Leases, Operating [Abstract]
Operating Lease, Cost	$ 275	$ 760
Operating Lease, Payments		$ 552
Operating Lease, Weighted Average Remaining Lease Term	8 years 7 months 6 days	8 years 7 months 6 days
Operating Lease, Weighted Average Discount Rate, Percent	3.90%	3.90%

Commitments and Contingencies F

Commitments and Contingencies Future Lease Payments (Details) $ in Millions	Sep. 30, 2019USD ($)
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
2019	$ 198
2020	782
2021	693
2022	580
2023	477
Thereafter	1,978
Total future minimum lease payments	4,708
Less imputed interest	(758)
Total	$ 3,950

Business Combinations Narrative

Business Combinations Narrative (Details) $ in Millions	9 Months Ended
	Sep. 30, 2019USD ($)
Business Combinations [Abstract]
Payments to Acquire Businesses, Gross	$ 9,700
Acquired Finite-Lived Intangibles and Goodwill	8,600
Finite-lived Intangible Assets Acquired	1,951
Goodwill, Acquired During Period	$ 6,600

Business Combinations Acquired

Business Combinations Acquired Assets and Liabilities (Details) $ in Millions	Sep. 30, 2019USD ($)
Business Acquisition [Line Items]
Cash and Equivalents	$ 1,537
Accounts Receivable and Other Current Assets	1,775
Property, Equipment and other long-term assets	1,941
Medical costs payable	(868)
Accounts Payable and other current liabilities	(1,669)
Other long-term liabilities	(1,283)
Total Net Tangible Liabilities	$ 1,433

Business Combinations Acquire_2

Business Combinations Acquired Finite-Lived Intangible Assets (Details) $ in Millions	9 Months Ended
	Sep. 30, 2019USD ($)
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-lived Intangible Assets Acquired	$ 1,951
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	13 years
Customer-Related Intangible Assets [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-lived Intangible Assets Acquired	$ 1,670
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	14 years
Trademarks and Technology [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-lived Intangible Assets Acquired	$ 117
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	4 years
Other Intangible Assets [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-lived Intangible Assets Acquired	$ 164
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	10 years

Segment Financial Information_3

Segment Financial Information (Narrative) (Details) $ in Millions	3 Months Ended
	Sep. 30, 2019USD ($)	Dec. 31, 2018USD ($)
Statement [Line Items]
Number of Reportable Segments	4
Assets	$ 173,709	$ 152,221
Optumhealth
Statement [Line Items]
Assets	40,100	29,800
Optuminsight
Statement [Line Items]
Assets	$ 15,100	$ 11,000

Segment Financial Information_4

Segment Financial Information (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement [Line Items]
Premiums, revenues - unaffiliated customers	$ 47,397	$ 44,613	$ 142,074	$ 133,155
Products, revenues - unaffiliated customers	7,546	7,344	23,971	21,050
Services, revenues - unaffiliated customers	4,942	4,217	13,756	12,590
Investment and other income	466	382	1,453	1,035
Total revenues	60,351	56,556	181,254	167,830
Earnings from operations	5,014	4,590	14,590	12,847
Interest expense	(449)	(353)	(1,267)	(1,026)
Earnings before income taxes	4,565	4,237	13,323	11,821
Optum
Statement [Line Items]
Investment and other income	192	140	549	402
Total revenues	28,763	25,391	83,152	73,718
Earnings from operations	2,359	2,031	6,339	5,531
Interest expense	0	0	0	0
Earnings before income taxes	2,359	2,031	6,339	5,531
Unaffiliated Customers
Statement [Line Items]
Premiums, revenues - unaffiliated customers	47,397	44,613	142,074	133,155
Products, revenues - unaffiliated customers	7,546	7,344	23,971	21,050
Services, revenues - unaffiliated customers	4,942	4,217	13,756	12,590
Total revenues	59,885	56,174	179,801	166,795
Unaffiliated Customers | Optum
Statement [Line Items]
Premiums, revenues - unaffiliated customers	1,840	985	3,986	2,794
Products, revenues - unaffiliated customers	7,546	7,344	23,971	21,050
Services, revenues - unaffiliated customers	2,668	2,150	7,153	6,342
Total revenues	12,054	10,479	35,110	30,186
Affiliated Customers
Statement [Line Items]
Total revenues	0	0	0	0
Affiliated Customers | Optum
Statement [Line Items]
Total revenues	16,517	14,772	47,493	43,130
Operating Segments | UnitedHealthcare
Statement [Line Items]
Investment and other income	274	242	904	633
Total revenues	48,105	45,937	145,595	137,242
Earnings from operations	2,655	2,559	8,251	7,316
Interest expense	0	0	0	0
Earnings before income taxes	2,655	2,559	8,251	7,316
Operating Segments | OptumHealth
Statement [Line Items]
Investment and other income	170	125	488	355
Total revenues	8,133	6,052	21,994	17,752
Earnings from operations	748	622	2,062	1,680
Interest expense	0	0	0	0
Earnings before income taxes	748	622	2,062	1,680
Operating Segments | OptumInsight
Statement [Line Items]
Investment and other income	6	4	17	15
Total revenues	2,617	2,254	7,145	6,508
Earnings from operations	632	534	1,589	1,382
Interest expense	0	0	0	0
Earnings before income taxes	632	534	1,589	1,382
Operating Segments | OptumRx
Statement [Line Items]
Investment and other income	16	11	44	32
Total revenues	18,454	17,437	55,194	50,484
Earnings from operations	979	875	2,688	2,469
Interest expense	0	0	0	0
Earnings before income taxes	979	875	2,688	2,469
Operating Segments | Unaffiliated Customers | UnitedHealthcare
Statement [Line Items]
Premiums, revenues - unaffiliated customers	45,557	43,628	138,088	130,361
Products, revenues - unaffiliated customers	0	0	0	0
Services, revenues - unaffiliated customers	2,274	2,067	6,603	6,248
Total revenues	47,831	45,695	144,691	136,609
Operating Segments | Unaffiliated Customers | OptumHealth
Statement [Line Items]
Premiums, revenues - unaffiliated customers	1,840	985	3,986	2,794
Products, revenues - unaffiliated customers	6	13	23	37
Services, revenues - unaffiliated customers	1,487	1,196	4,131	3,587
Total revenues	3,333	2,194	8,140	6,418
Operating Segments | Unaffiliated Customers | OptumInsight
Statement [Line Items]
Premiums, revenues - unaffiliated customers	0	0	0	0
Products, revenues - unaffiliated customers	29	29	74	72
Services, revenues - unaffiliated customers	988	790	2,532	2,306
Total revenues	1,017	819	2,606	2,378
Operating Segments | Unaffiliated Customers | OptumRx
Statement [Line Items]
Premiums, revenues - unaffiliated customers	0	0	0	0
Products, revenues - unaffiliated customers	7,511	7,302	23,874	20,941
Services, revenues - unaffiliated customers	193	164	490	449
Total revenues	7,704	7,466	24,364	21,390
Operating Segments | Affiliated Customers | UnitedHealthcare
Statement [Line Items]
Total revenues	0	0	0	0
Operating Segments | Affiliated Customers | OptumHealth
Statement [Line Items]
Total revenues	4,630	3,733	13,366	10,979
Operating Segments | Affiliated Customers | OptumInsight
Statement [Line Items]
Total revenues	1,594	1,431	4,522	4,115
Operating Segments | Affiliated Customers | OptumRx
Statement [Line Items]
Total revenues	10,734	9,960	30,786	29,062
Optum Eliminations
Statement [Line Items]
Investment and other income	0	0	0	0
Total revenues	(441)	(352)	(1,181)	(1,026)
Earnings from operations	0	0	0	0
Interest expense	0	0	0	0
Earnings before income taxes	0	0	0	0
Optum Eliminations | Unaffiliated Customers
Statement [Line Items]
Premiums, revenues - unaffiliated customers	0	0	0	0
Products, revenues - unaffiliated customers	0	0	0	0
Services, revenues - unaffiliated customers	0	0	0	0
Total revenues	0	0	0	0
Optum Eliminations | Affiliated Customers
Statement [Line Items]
Total revenues	(441)	(352)	(1,181)	(1,026)
Corporate and Eliminations
Statement [Line Items]
Investment and other income	0	0	0	0
Total revenues	(16,517)	(14,772)	(47,493)	(43,130)
Earnings from operations	0	0	0	0
Interest expense	(449)	(353)	(1,267)	(1,026)
Earnings before income taxes	(449)	(353)	(1,267)	(1,026)
Corporate and Eliminations | Unaffiliated Customers
Statement [Line Items]
Premiums, revenues - unaffiliated customers	0	0	0	0
Products, revenues - unaffiliated customers	0	0	0	0
Services, revenues - unaffiliated customers	0	0	0	0
Total revenues	0	0	0	0
Corporate and Eliminations | Affiliated Customers
Statement [Line Items]
Total revenues	$ (16,517)	$ (14,772)	$ (47,493)	$ (43,130)